Measuring Yellowstone’s Power

A 17-year long study by geologists at the University of Utah using GPS antennas to accurately measure ground movement in the Yellowstone Caldera has revealed that the hotspot is responsible for much more movement than originally thought.

Other surprising results show that southwestern part of the Yellowstone Plateau is sliding toward the southwest at a rate of a sixth of an inch per year. Also, the surface along the Teton Fault is moving in the opposite direction that was expected.

The Teton Fault is capable of producing a M7.0 to M7.5 earthquake, however the last such event was roughly 5,000 years ago. The newly observed movement along the fault may explain how pressure is built up and/or relieved due to the Yellowstone hotspot.

The study also shows interesting measurements within the caldera itself, with the floor rising and falling. From 2000 to 2003, the caldera floor sank about 1.1 inches. However since 2004, the central portion of the caldera has risen an incredible 6.7 inches, faster than ever previously recorded.

From the article:

The fact some GPS receivers now are permanently installed in Yellowstone and provide data daily made researchers realize that ups-and-downs of the caldera occur not just in decades or years, but in months, reflecting underground movements of molten rock and hot water that also happen over months.